To extend the application of the swashplate engine from special engines to the field of general power machinery， it is necessary to considerate speed stability， dynamic balance performance and manufacturing， etc. A new swashplate engine is designed， it used the nutation movement of a pair of spiral bevel gears to drive the body of the swashplate engine to rotate， so that there is a relative angular displacement between the cylinder cover and the cylinder， and then the differential speed distribution is realized. This scheme not only eliminates the planetary gear system and reduces the kinetic energy loss， but also uses arc bevel gear instead of traditional straight bevel gear to reduce vibration and noise， and the distribution system layout is optimized. A three-dimensional model built with SolidWorks is simulated and comparative analyzed by the Adams platform. The results show that the presented structure scheme has a better stable performance of rotating speed and can effectively control vibration than the conventional straight bevel gear mechanism.